Carbonated cola beverages are sold in 12 ounce metal containers which are pressurized and sealed by an origianl factory closure lid. A common beverage container in widespread use is the seamless, extruded aluminum can which includes a sealing lid joined to a cylindrical sidewall along a rolled, annular rim. The closure lid is scored along a line which defines the outline of a dispensing opening. A metal opening tab is attached to the lid for rupturing the lid along the score line. The scored segment is displaced into the interior of the can upon opening and cannot be resealed.
Carbonated beverages contain dissolved carbon dioxide gas which will escape into the atmosphere unless the container is pressurized and sealed. The flavor of such carbonated beverages turns flat in the absence of the dissolved carbon dioxide gas. The loss of dissolved carbonation can be reduced somewhat by sealing the beverage container after use.
The extruded aluminum can having a closure lid which is punctured for dispensing purposes is disposable and not intended to be resealed. Unless the beverage is consumed within a short time after opening, the carbonation will be released, with the result that the flavor of the remaining beverage is impaired. Accordingly, the quality of the remaining beverage will gradually deteriorate with the result that the remaining beverage will become unpalatable, and will be discarded.
There are occasions when it is not convenient or desirable to consume the entire contents while the beverage is fresh. One reason for this is that the 12 ounce volume of the carbonated beverage may be substantially more than is wanted or needed. Children may open a beverage can and consume only a limited amount which satisfies their needs for the moment. Others, including adults, may find it convenient or desirable to use only a portion of the beverage contents, for example as a mixer. In such instances, the remaining portion of the carbnonated beverage will quickly become flat and unpalatable. For that reason, it is customary to discard any carbonated beverage which may be left over and not consumed within an hour or so after the dcarbonated beverage container has been opened.